php - 搜索一个字符串是否存在于另一个字符串中

Question

为了我的目的，我这样做了:

<?php
$mystring = 'Gazole,';
$findme   = 'Sans Plomb 95';
$pos = strpos($mystring, $findme);

if ($pos >= 0) {
    echo "The string '$findme' was found in the string '$mystring'";
    echo " and exists at position $pos";
} else {
    echo "The string '$findme' was not found in the string '$mystring'";
}
?>

但是，它总是执行这个分支:

echo "The string '$findme' was found in the string '$mystring'";
echo " and exists at position $pos";

虽然我要搜索的字符串不存在。

请提前帮忙，thx :))

Answer 1

正确的做法是:

if ($pos !== false) {
    echo "The string '$findme' was found in the string '$mystring'";
    echo " and exists at position $pos";
} else {
    echo "The string '$findme' was not found in the string '$mystring'";
}

参见 giant red warning在文档中。